Staff Software Engineer, Frontend - Fintech Platform (m/f/n)

InPost Pay is building its own fintech platform from the ground up as a large-scale, international initiative. They are building a lean, highly effective engineering organization in Poland with AI-native engineering at its core.

• 8+ years in software engineering including 2+ years in cross-team technical leadership or architecture authority
• 3+ years building customer-facing or merchant-facing products in payments or fintech
• Expert-level experience with a modern frontend framework (e.g. React) and TypeScript at scale
• Design-system and component architecture experience across multiple teams or products
• Experience with micro-frontend architecture and client-side state management patterns
• Performance engineering knowledge: Core Web Vitals, bundle optimization, rendering-strategy trade-offs (SSR / CSR / ISR)
• Accessibility standards (WCAG) integrated into architecture
• API consumption patterns including REST, GraphQL, async, and event-based contracts
• Experience designing or evolving an agentic engineering harness for frontend workflows with instrumentation and adoption measurement
• Excellent technical writing skills for ADRs, RFCs, and design docs
• English proficiency at B2 or above
• University degree in Computer Science, IT, or related field

Nice to have:

• 2+ years in platform or internal developer tooling engineering
• 1+ years of agentic/LLM system design experience
• 2+ years experience in BNPL or lending domain products
• Mobile app architecture (e.g. React Native) alongside web
• Real-time UI patterns (WebSockets, streaming updates)
• Internationalisation / localisation architecture at scale
• Open-source contributions or technical publishing
• Polish language skills

• Define and maintain frontend architecture: component architecture, design-system boundaries, micro-frontend patterns, client-side state management, and performance budgets across teams
• Author Architecture Decision Records (ADRs) and RFCs with documented reasoning and trade-off analysis
• Evaluate and decide on frontend technology trade-offs including framework/library selection, build tooling, rendering strategy (SSR / CSR / ISR), and accessibility standards
• Own evolution of agentic development harness for frontend workflows: instrumentation, measurement, and improvements based on data
• Drive frontend technical change organization-wide: identify patterns and components to adopt or deprecate and support adoption across teams without direct authority
• Provide technical input to product strategy; mentor Staff-track engineers through design reviews, pairing, and technical writing feedback